Smart portable devices like smart phones, tablet computers and pad-shape devices are generally used and theirs usage is increasing. The size of the displays of them is also increasing together. In these days, touch devices having big size of displays larger than 5-inch are mainly being developed and theses trends seem like to be maintained for a long time.
The 5-inch or larger size of mobile device doesn't permit only one hand all around touch. Actually an adult man can not touch all the area of the large touch screen, by using only one hand which grip the device.
When a user cannot help but use only one hand to handle a device, there may be an accident caused by the user's careless mistake.
To overcome these problems, Korean published patent No. 10-2011-0018589 and Korean published patent No. 10-2012-0127649 disclose methods to reduce the size of the display or skew the arrangement of the icons, which cannot resolve all the inconvenience.